Mobile communication terminal for PTT and method for processing missed call information thereof

ABSTRACT

The present invention relates to a mobile communication terminal for Push To Talk (PTT) and a method for processing missed call information thereof, which allows a receiver to check why an originator requested the PTT telephone call during the absence of the receiver through missed call information. The missed call information includes the voice of the originator requesting the PTT call, and the voice of the originator is output when confirmation of the missed call information is requested.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is continuation of U.S. patent application Ser.No. 14/507,495, filed on Oct. 6, 2014, which is a continuation of U.S.patent application Ser. No. 11/947,476, filed on Nov. 29, 2007, andclaims priority from and the benefit of Korean Patent Application No.10-2007-0033094, filed on Apr. 4, 2007, each of which is herebyincorporated by reference for all purposes as if fully set forth herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a mobile communication terminal and amethod for processing information thereof, and more particularly, to amobile communication terminal that performs Push To Talk (PTT)communication and a method for processing information of a missed call.

2. Discussion of the Background

Developments in mobile communication technology and manufacturingtechnology for mobile communication terminals have resulted in mobilecommunication terminals that are capable of performing various functionswith simple portability. In particular, mobile communication terminalsequipped with PTT communication modules have recently been introduced.

Here, PTT communication refers to a communication method of a wirelesstelephone set, and it is one of wireless communication methods by whicha user can perform a conversation. The user may perform a conversationby pressing down a PTT key prepared in the wireless telephone set whenthe user is talking to another party and releasing the PTT key when theuser is listening to the other party. PTT communication may provide amultipoint wireless communication service as well as one-to-one service.

In particular, as to the mobile communication terminal, PTTcommunication service can be provided using Voice over IP (VoIP) afterassigning an intrinsic Internet Protocol (IP) address. A conversationbetween mobile communication terminals for PTT begins when theoriginator requests a PTT telephone call by pressing down a PTT key. PTTconversation may be performed when the receiver responds to the receivedPTT telephone call by pressing down a PTT key.

When the receiver does not receive the PTT call, the receiver's mobilecommunication terminal stores the missed call information. When thereceiver activates the mobile communication terminal for PTT, the missedcall information that has not be confirmed by the user may be displayedin a display unit. The missed call information may include theoriginator information and the time at which the missed call occurred.The originator information may be the phone number of the originator orthe name of the originator.

Therefore, as the missed call information of the related art includesonly the originator information and the time at which the missed calloccurred, the receiver is notified only that there has been a missedcall and cannot know the reason why the originator requested a PTTtelephone call from the missed call information.

SUMMARY OF THE INVENTION

The present invention provides a mobile communication terminal for PTTcommunication and a method for processing information of a missed callthat allows a receiver to check why the originator of the missed callrequested the PTT telephone call.

The present invention further provides a mobile communication terminalfor PTT communication and a method for processing information of amissed call, in which missed call information including the voice of anoriginator requesting a PTT call is stored and the voice of theoriginator is output when confirmation of the missed call information isrequested.

Additional features of the invention will be set forth in thedescription which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention.

The present invention discloses a method of processing information of amissed PTT including buffering the voice of an originator of a PTT call,determining whether the PTT call is a missed call, storing missed callinformation including the buffered voice when it is determined that thePTT call is a missed call, and outputting the buffered voice included inthe missed call information in response to a request for confirmation ofthe missed call information is requested.

The present invention also discloses a mobile communication terminal forPTT including a PTT communications module, a voice processor, abuffering unit, a missed call determining unit, a storage, and a PTTtelephone call controller. The PTT communications module performs PTTcommunication. The voice processor processes the voice of an originatorof a PTT call, which the PTT communications module received, and outputsthe processed voice. The buffering unit buffers the voice of theoriginator. The missed call determining unit determines whether a missedcall has occurred. The storage stores missed call information includingthe buffered voice when it is determined that a missed call occurred.The PTT telephone call controller outputs the buffered voice included inthe missed call information when confirmation of the missed callinformation is requested.

The present invention also discloses a method of processing a missedcall information of a mobile communications terminal for PTT includingstoring missed call information including the voice of an originatorrequesting a PTT call in a standby state, displaying a list ofunconfirmed missed call information among the stored missed callinformation when the standby state is converted to an active state, andoutputting the voice of the originator included in selected missed callinformation when unconfirmed missed call information is selected.

The present invention also includes a mobile communications terminal forPTT including a voice processor, a storage, a display unit, and a PTTtelephone call controller. The voice processor receives a PTT call in astandby state, processes the voice of an originator of the PTT call, andoutputs the processed voice. The storage stores missed call informationincluding the voice of the originator when a missed call occurs. Thedisplay unit displays a list of unconfirmed missed call informationamong the stored missed call information when the standby state isconverted to an active state. The PTT telephone call controller outputsthe voice of the originator included in selected missed call informationwhen unconfirmed missed call information is selected.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention, andtogether with the description serve to explain the principles of theinvention.

FIG. 1 shows the configuration of a PTT communication system using amobile communication terminal for PTT according to an exemplaryembodiment of the present invention.

FIG. 2 is a block diagram showing the configuration of a mobilecommunication terminal for PTT of FIG. 1.

FIG. 3 shows an example of a screen that shows the procedure of settingup a missed call mode in the method of processing a missed call of amobile communication terminal for PTT according to an exemplaryembodiment of the present invention.

FIG. 4A and FIG. 4B are flowcharts showing the storage process of amissed call in the processing method of a missed call of a mobilecommunication terminal for PTT according to an exemplary embodiment ofthe present invention.

FIG. 5 is a flowchart showing the process of displaying missed callinformation in the method of processing a missed call of a mobilecommunication terminal for PTT according to an exemplary embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The invention is described more fully hereinafter with reference to theaccompanying drawings, in which embodiments of the invention are shown.This invention may, however, be embodied in many different forms andshould not be construed as limited to the embodiments set forth herein.Rather, these embodiments are provided so that this disclosure isthorough, and will fully convey the scope of the invention to thoseskilled in the art. Like reference numerals in the drawings denote likeelements.

Here, a mobile communication terminal for PTT is a mobile communicationterminal that performs PTT communication and may include a digitalbroadcast terminal, Personal Digital Assistant (PDA), a smart phone, anInternational Mobile Telecommunication 2000 (IMT-2000) terminal, aWideband Code Division Multiple Access (WCDMA) terminal and an UniversalMobile Telecommunication Service (UMTS) terminal.

FIG. 1 is a drawing showing the configuration of a PTT communicationsystem 100 using mobile communication terminals for PTT 10 a, 10 baccording to an exemplary embodiment of the present invention.

Referring to FIG. 1, the PTT communication system 100 may include amobile communication terminal for PTT for the outgoing side 10 a, amobile communication terminal for PTT for the receiving side 10 b, and aPTT server 40. Here, the mobile communication terminals for PTT for theoutgoing side and the receiving side 10 a, 10 b are coupled to the PTTserver 40 through a wireless communication network 30 to perform a PTTcall.

The wireless communication network 30 may include a Mobile SwitchingCenter (MSC) and a Base Station (BS) Transceiver System. The BSTransceiver System performs communications with multiple mobilecommunication terminals for PTT 10 a, 10 b positioned in a correspondingservice area and is coupled to the MSC through a Base Station Controller(BSC). The MSC is coupled to the PTT server 40 through a data network.

The PTT server 40 performs arbitration, performs maintenance of PTTcommunication requests, distributes the registration list by eachsubscriber, and manages the real time operation of a PTT user groupincluding the connection and release of a call of a necessary system anda network resource as well as an overall control operation for the PTTuser group.

Accordingly, the PTT server 40 delivers voice output from the mobilecommunication terminal for PTT for the outgoing side 10 a to the mobilecommunication terminal for PTT for the receiving side 10 b through thewireless communication network 30.

The PTT server 40 performs a PTT telephone call with the mobilecommunication terminal for PTT for the outgoing side 10 a according tothe selection of a PTT key 13 a of the mobile communication terminal forPTT for the receiving side 10 b.

In this case, as to the configuration of the PTT communication system100 according to an exemplary embodiment of the present invention, themobile communication terminals for PTT shown in FIG. 2 may be the mobilecommunication terminals for PTT for the outgoing side 10 a or for thereceiving side 10 b. However, for convenience, the mobile communicationterminal for PTT for the receiving side 10 b, which receives the missedcall, is used to describe the mobile communication terminal for PTT 10shown in FIG. 2.

FIG. 2 is a block diagram showing the configuration of a mobilecommunication terminal for PTT 10 of FIG. 1. Referring to FIG. 1 andFIG. 2, the mobile communication terminal for PTT 10 according to theexemplary embodiment of the present invention includes a controller 12,a key input unit 13, storage 14, a wireless communication unit 15, avoice processor 16, and a display unit 17.

Here, the mobile communication terminal for PTT 10 can be used as amobile communication terminal for PTT for the outgoing side 10 a or thereceiving side 10 b. However, in exemplary embodiments of the presentinvention, it is exemplified that the mobile communication terminal forPTT is used as the receiving side, which receives a missed call.

The controller 12 performs the overall control operation of the mobilecommunication terminal for PTT 10. The controller 12 processes missedcall information of a received PTT call. The key input unit 13 providesa plurality of keys for the manipulation of the mobile communicationterminal for PTT 10 and generates a key data according to the keyselection of the user to deliver it to the controller 12. The key inputunit 13 includes a PTT key 13 a that performs PTT communications and, inaddition, may include a function key such as a cancel key, aconfirmation key, a numeric key, a 4-direction key, and/or an end key.Various input means including a key pad, a touch screen, and a touch padcan be used as a key input unit 13.

The storage 14 stores a program that is necessary for controlling theoperation of the mobile communication terminal for PTT 10 and storesdata that is generated during the execution of the program. The storage14 also stores an executive program for performing a PTT telephone calland an executive program for processing missed call information. Thestorage 14 includes setting information 14 a of the missed call andmissed call information 14 b. Here, the missed call information 14 bincludes an originator phone number and the time at which the missedcall occurred and may further include voice information of theoriginator.

The wireless communication unit 15 modulates and performs frequencytranslation for the data output from the controller 12 and sends awireless signal through an antenna ANT. Further, the wirelesscommunication unit 15 separates a received signal from a wireless signalreceived through the antenna ANT. Particularly, the wirelesscommunication unit 15 transceives a voice for PTT call.

The voice processor 16 digitalizes the voice input through a microphoneMIC under the control of the controller 12 and demodulates the voicedata received through the wireless communication unit 15 to output itthrough a speaker SPK. During a PTT call, the voice processor 16 outputsthe voice of the originator, which is received through the wirelesscommunication unit 15, through the speaker SPK and receives the voice ofthe receiver through the microphone MIC to output it to the mobilecommunication terminal for PTT for the outgoing side 10 a through thewireless communication unit 15. Particularly, the voice processor 16outputs the voice included in the missed call information 14 b whenconfirming the missed call information 14 b.

The display unit 17 displays information stored in the storage 14 inaddition to various function menus executed in the mobile communicationterminal for PTT 10. The display unit 17 displays a setting menu ofsetting information in a user's absence, setting information 14 a, andmissed call information 14 b. In this case, a Liquid Crystal Display(LCD) or a touch screen can be used as display unit 17. The touch screenmay simultaneously play a role of a display unit and an input device.Particularly, the controller 12 performs a PTT call and processes missedcall information for the received PTT call. The controller 12 includes aPTT communication module 12 a, a missed call mode setting unit 12 b, abuffering unit 12 c, a missed call determining unit 12 d, and a PTTtelephone call controller 12 e. The PTT communication module 12 aperforms PTT communication. During PTT communication, the voiceprocessor 16 processes the voice of the originator of the PTT telephonecall that the PTT communication module 12 a received and outputs it tothe speaker SPK.

The missed call mode setting unit 12 b sets a time for buffering thevoice of the originator of a PTT telephone call according to the keyinput of the user and sets the maximum storage number for missed callinformation. In this case, the buffering time may be several seconds toseveral tens of seconds. The maximum storage number for missed callinformation may be within the total capacity of the storage 14.

The buffering unit 12 c buffers the voice of the originator of thereceived PTT telephone call within the set buffering time. When thebuffering time is over, the buffer 12 c stops buffering.

The missed call determining unit 12 d determines whether there is aresponse to the received PTT call. When there is no response, the missedcall determining unit 12 d determines that a missed call has occurred.The missed call determining unit 12 d determines whether there is aresponse according to the selection of the PTT key 13 a and determinesif a missed call has occurred according to whether there is a response.

When it is determined that there is a missed call, the PTT telephonecall controller 12 e stores the missed call information 14 b, includingthe buffered voice, in the storage 14 for the received PTT call. Whenconfirmation of the missed call information 14 b is requested from thePTT telephone call controller 12 e, the voice included in the requestedmissed call information 14 b is output to the voice processor 16. ThePTT telephone call controller 12 e displays the originator informationand the time when the missed call occurred among the requested missedcall information 14 b on the display unit 17. The PTT telephone callcontroller 12 e can delete the missed call information 14 b includingthe voice of the originator once it is confirmed by key input throughthe key input unit 13.

The PTT telephone call controller 12 e determines the storage number ofthe missed call information 14 b and determines whether the storagenumber of the missed call information 14 b is less than or equal to themaximum storage number. When it is determined that the storage numberexceeds the maximum storage number, the PTT telephone call controller 12e does not buffer the voice of the originator of the PTT telephone call,which is received through the buffering unit 12 c. Therefore, when thestorage number of the missed call information 14 b exceeds the maximumstorage number, the PTT telephone call controller 12 e stores only theoriginator phone number and the time when the missed call occurred asmissed call information 14 b.

On the other hand, when it is determined by the missed call determiningunit 12 d that a response has occurred, the PTT telephone callcontroller 12 e deletes the buffered voice and performs the PTTtelephone call with the mobile communications terminal for PTT for theoutgoing side 10 a through the PTT communication module 12 a.

Therefore, as to the mobile communications terminal 10 for PTT accordingto an exemplary embodiment of the present invention, if missed callinformation is generated for a received PTT call, the voice of theoriginator of the received PTT telephone call is stored in the missedcall information 14 b. If confirmation of the missed call information 14b is requested, the voice of the originator included in the missed callinformation 14 b is output. Therefore, by hearing the voice of theoriginator, a receiver may be able to determine why the originatorrequested the PTT call.

FIG. 3 is a drawing showing an example of a screen that shows theprocedure of setting up a missed call mode in the method of processing amissed call of a mobile communication terminal for PTT according to anexemplary embodiment of the present invention. Referring to FIG. 1, FIG.2, and FIG. 3, the setup procedure of the missed call mode will beshown.

Firstly, as shown in FIG. 3( a), when the setup menu of the missed callmode is selected according to the key selection of the key input unit13, the missed call mode setting unit 12 b displays a setup menu 21 onthe display unit 17. At this time, the setup menu 21 includes a functionsetting menu, a buffering time setting menu, and a storage numbersetting menu as a lower menu, while the lower menu can be displayed as alist of the text base.

A lower menu can be selected using a numeric key of the key input unit13. Otherwise, a 4-direction key of the key input unit 13 may bemanipulated to position a focus 25 at the lower menu to be selected, anda verification key may be pressed to select the focused lower menu. Whena specific lower menu is displayed and the cancel key of the key inputunit 13 is pressed, the missed call mode setting unit 12 b displays asetup menu 17.

As shown in FIG. 3( b), when the function setting menu is selectedthrough the key selection of the key input unit 13, the missed call modesetting unit 12 b displays a function setting menu 22 on the displayunit 17. The items of the function setting menu 22 are “ON” and “OFF”.Here, if “OFF” is selected, the missed call mode setting unit 12 binactivates the processing function of the missed call informationaccording to an exemplary embodiment of the present invention. However,if “ON” is selected, the missed call mode setting unit 12 b beginsprocessing the missed call information according to an exemplaryembodiment of the present invention. At this time, according to the setup buffering time and the set up storage number, the PTT telephone callcontroller 12 e performs the processing function of the missed callinformation.

As shown in FIG. 3( c), when the buffering time setting menu is selectedthrough key selection of the key input unit 13, the missed call modesetting unit 12 b displays a buffering time setting menu 23 on thedisplay unit 17. In the buffering time setting menu 23, a numeric key ofthe key input unit 13 may be pressed to input a set buffering time.

As shown in FIG. 3( d), when the storage number setup menu is selectedby key selection of the key input unit 13, the missed call mode settingunit 12 b displays a storage number setup menu 24 on the display unit17. In the storage number setup menu 24, a numeric key of the key inputunit 13 may be pressed to input a maximum storage number.

In the present exemplary embodiment, the example in which the lowermenus were displayed on the setup menu 21 as text was disclosed.However, the lower menus can be displayed as icons.

FIG. 4A and FIG. 4B are flowcharts showing the process of storing amissed call in the processing method of a missed call of a mobilecommunication terminal for PTT according to an exemplary embodiment ofthe present invention.

Referring to FIG. 1, FIG. 2, FIG. 4A and FIG. 4B, the process of storingmissed call information 14 b will be shown. At this time, the mobilecommunication terminal 10 b for PTT for the receiving side is in a statein which the processing function of the missed call information isactivated.

Initially, the mobile communications terminal for PTT for the receivingside 10 b is in a standby state (S51). Then the PTT telephone callcontroller 12 e determines whether a PTT telephone call has beenreceived (S52). When it is determined that a PTT telephone call has notbeen received, the PTT telephone call controller 12 e maintains thestandby state (S51). When it is determined that a PTT telephone call hasbeen received, the PTT telephone call controller 12 e determines whetherthe storage number of the missed call information 14 b is less than orequal to the maximum storage number (S53).

When it is determined that the maximum storage number has not beenexceeded, the buffering unit 12 c buffers the voice of the originator ofthe received PTT telephone call under the control of the PTT telephonecall controller 12 e (S54). The process when it is determined that themaximum storage number has been exceeded will be described below.

In step S55, the missed call determining unit 12 d determines theresponse of the receiving side for the received PTT call. When it isdetermined that a response has occurred, the PTT telephone callcontroller 12 e deletes the buffered voice and performs the PTTtelephone call with the mobile communication terminal for PTT for theoutgoing side 10 a through the PTT communication module 12 a (S56).

On the other hand, when it is determined that there has been noresponse, the missed call determining unit 12 d determines whether thetime for which there has been no response exceeds the set buffering timeafter the PTT telephone call is received (S57).

If it is determined that the set buffering time has not been exceeded,the missed call determining unit 12 d determines whether a missed callhas occurred (S58). When it is determined that a missed call has notoccurred, the controller 12 again performs steps S54 to S57.

When it is determined that the set buffering time has been exceeded, thebuffering unit 12 c discontinues buffering the voice of the originatorof the received PTT telephone call under the control of the PTTtelephone call controller 12 e (S59).

The missed call determining unit 12 d determines whether there has beena missed call (S61). If it is determined that a missed call has notoccurred, the controller 12 again returns to step S55.

If it is determined that a missed call has occurred, the PTT telephonecall controller 12 e stores the missed call information 14 b includingthe buffered voice in the storage 14 (S62).

In step S63, the PTT telephone call controller 12 e determines thestorage number of the missed call information 14 b stored in the storage14. At this time, the PTT telephone call controller 12 e counts onlymissed call information 14 b including the voice of an originator.

Subsequently, the PTT telephone call controller 12 e determines thetermination according to the input of the end key (S64). When it isdetermined that the end key has not been input, the PTT telephone callcontroller 12 e returns to the standby state of step S51. On thecontrary, when it is determined that the end key has been input, the PTTtelephone call is terminated.

When it is determined, at step S53, that the maximum storage number hasbeen exceeded, the PTT telephone call controller 12 e does not buffer ofthe voice of an originator. In step S65, the missed call determiningunit 12 d determines whether there has been a response to the receivedPTT call.

When it is determined that there has been a response, the PTT telephonecall controller 12 e performs the PTT call with the mobilecommunications terminal for PTT for the outgoing side 10 a through thePTT communication module 12 a (S66).

At this time, the PTT telephone call controller 12 e does not have thebuffered voice. Therefore, it does not perform the process of deletingthe buffered voice. Subsequently, the PTT telephone call controller 12 eperforms step S64.

When it is determined that there has not been a response, the missedcall determining unit 12 d determines that a t missed call has occurred(S67).

When it is determined that a missed call has occurred, the PTT telephonecall controller 12 e stores the missed call information 14 b in thestorage 14 (S68). At this time, the stored missed call information 14 bincludes the originator phone number and the time when the missed calloccurred, but does not include the voice of an originator. Subsequently,the PTT telephone call controller 12 e performs step S64.

FIG. 5 is a flowchart showing the voice output of missed callinformation 14 b and the displaying process, in the method of processinga missed call of a mobile communication terminal for PTT 10 according toan exemplary embodiment of the present invention.

Initially, the mobile communications terminal for PTT for the receivingside 10 b is in a standby state (S71). Then, the PTT telephone callcontroller 12 e determines whether it is converted to an active state(S72). When it is determined that it has not been converted to theactive state, the PTT telephone call controller 12 e maintains thestandby state (S71).

Conversion into an active state is determined by key selection of thekey input unit 13. That is, when a special key or an arbitrary key ofthe key input unit 13 is selected in the standby state, the PTTtelephone call controller 12 e is converted from the standby state intothe active state.

When it is determined that there has been a conversion into the activestate, the PTT telephone call controller 12 e determines whetherunconfirmed missed call information 14 b exists among the missed callinformation 14 b stored in the storage 14 (S73).

When it is determined that unconfirmed missed call information does notexist, the controller 12 displays the wall paper on the display unit 17(S74).

If it is determined that unconfirmed missed call information 14 b doesexist, the PTT telephone call controller 12 e displays a list of theunconfirmed missed call information 14 b on the display unit 17 (S75).At this time, the PTT telephone call controller 12 e can display thelist of the unconfirmed missed call information 14 b with using text oricons on the display unit 17.

The PTT telephone call controller 12 e determines whether specificmissed call information 14 b among the list of the displayed missed callinformation has been selected. When it is determined that missed callinformation 14 b has not been selected, the PTT telephone callcontroller 12 e maintains the display mode of the missed callinformation list (S75).

When it is determined that missed call information 14 b has beenselected, the PTT telephone call controller 12 e determines whether theselected missed call information 14 b has a stored voice (S77).

If it is determined that a stored voice does not exist, the PTTtelephone call controller 12 e displays the missed call information 14 bon the display unit 17 (S78). At this time, the missed call information14 b displayed on the display unit 17 includes the originator phonenumber and the time when the missed call occurred.

When it is determined that a stored voice exists, the PTT telephone callcontroller 12 e outputs the voice that is stored among the missed callinformation 14 b to the speaker SPK through the voice processor 16(S79). The PTT telephone call controller 12 e displays the originatorphone number and the time when the missed call occurred on the displayunit 17.

The PTT telephone call controller 12 e determines whether there has beena delete request of the confirmed missed call information 14 b (S81).When it is determined that there has been a delete request, the PTTtelephone call controller 12 e deletes the confirmed missed callinformation 14 b (S82). Further, when the missed call information 14 bto be deleted includes the voice of an originator, the PTT telephonecall controller 14 b reduces the storage number.

Then, the PTT telephone call controller 12 e determines whetherunconfirmed missed call information 14 b exists. Further, when it isdetermined that there has not been a delete request, the PTT telephonecall controller 12 e performs step S83.

If it is determined that unconfirmed missed call information 14 bexists, the PTT telephone call controller 12 e starts again from stepS75. On the other hand, if it is determined that unconfirmed missed callinformation 14 b does not exist, the PTT telephone call controller 12 eterminates the voice output and the display process of the missed callinformation 14 b.

In the present exemplary embodiment, an example of confirming theunconfirmed missed call information was disclosed. However, whenreaffirmation of missed call information stored in the storage isrequired, even if it is already confirmed, the PTT telephone callcontroller may output the voice of the originator included in the missedcall information, which is requested for a reaffirmation, through thevoice processor.

According to exemplary embodiments of the present invention, a PTT callis received and the voice of an originator is buffered. When a missedcall occurs, missed call information including the buffered voice isstored. When confirmation of the missed call information is requested,the voice of an originator included in the missed call information isoutput. Therefore, a receiver can confirm the voice of an originator inverifying the missed call information. Accordingly, a receiver may beable to determine why the originator requested the PTT call.

In addition, when the receiver does not respond to the PTT call within apredetermined time, the originator can leave a short voice message anddiscontinue the PTT call. In this case, the receiver can confirm theshort voice message of the originator through the missed callinformation.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the spirit or scope of the invention. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed:
 1. A method of processing missed call information at amobile communication terminal for Push To Talk (PTT), comprising:buffering a voice of an originator of the PTT call in response toreceiving a PTT call; identifying whether a response to the PTT call isgenerated within a time interval; storing missed call informationincluding the buffered voice if the response is not generated within thetime interval; outputting the buffered voice included in the storedmissed call information in response to a request corresponding to themissed call information; and in response to the request or if theresponse to the PTT call is generated within the time interval, deletingthe buffered voice.
 2. The method of claim 1, wherein the voice of theoriginator is buffered for a predetermined time.
 3. The method of claim1, wherein the missed call information further includes at least one oforiginator information and a time when the missed call occurred.
 4. Themethod of claim 1, wherein the response to the PTT call is generated byan user input to a PTT key attached to the mobile communicationterminal.
 5. The method of claim 1, further comprising setting a timefor buffering the voice of the originator according to an user input. 6.The method of claim 1, further comprising setting a maximum storagenumber for storing missed call information according to an user input.7. The method of claim 6, further comprising identifying whether astorage number of missed call information exceeds the maximum storagenumber.
 8. The method of claim 7, further comprising storing at leastone of originator phone number and a time when missed call occurredwithout storing the buffered voice, if the response is not generatedwithin the time interval and the storage number of missed callinformation exceeds the maximum storage number.
 9. The method of claim1, further comprising setting a storage capacity for storing missed callinformation according to an user input.
 10. The method of claim 1,wherein the request comprises an user input to a key input unit includedin the mobile communication terminal.
 11. A mobile communicationterminal for Push To Talk (PTT), comprising: a PTT communications moduleconfigured to receive a PTT call; a buffering unit configured to buffera voice of an originator of the PTT call in response to receiving thePTT call; and a controller configured to identify whether a response tothe PTT call is generated within a time interval, store missed callinformation including the buffered voice if the response is notgenerated within the time interval, output the voice included in thestored missed call information in response to a request corresponding tothe missed call information, and, in response to the request or if theresponse to the PTT call is generated within the time interval, deletethe buffered voice.
 12. The mobile communication terminal for PTT ofclaim 11, wherein the voice of the originator is buffered for apredetermined time.
 13. The mobile communication terminal for PTT ofclaim 11, wherein the missed call information further includes at leastone of originator information and a time when the missed call occurred.14. The mobile communication terminal for PTT of claim 11, furthercomprising: a PTT key used to perform the PTT communications, whereinthe response to the PTT call is generated by an user input to the PTTkey.
 15. The mobile communication terminal for PTT of claim 11, whereinthe controller is further configured to set a time for buffering thevoice of the originator according to an user input.
 16. The mobilecommunication terminal for PTT of claim 11, wherein the controller isfurther configured to set a maximum storage number for storing missedcall information according to an input.
 17. The mobile communicationterminal for PTT of claim 16, wherein the controller is furtherconfigured to identify whether a storage number of missed callinformation exceeds the maximum storage number.
 18. The mobilecommunication terminal for PTT of claim 17, wherein the controller isfurther configured to store the missed call information including theoriginator phone number and a time when the missed call occurred withoutstoring the buffered voice, if the response is not generated within thetime interval and the storage number of missed call information exceedsthe maximum storage number.
 19. The mobile communication terminal forPTT of claim 11, wherein the controller is configured to set a storagecapacity for storing missed call information according to an input. 20.The mobile communication terminal for PTT of claim 11, furthercomprising: a key input unit, wherein the request comprises an userinput to the key input unit.